Storms

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3551.55 Adler

Ad5s US1255048

PUBLIC LIBRARY FORT WAYNE AND ALLEN COUNTY, IND.

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Storms

3 833 00578 51 5

The “Reason Why” Series

STORMS Irving and Ruth Adler

The John Day Company

New York

The “Reason Why” Series by Irving and Ruth Adler

AIR INSECTS AND PLANTS NUMBERS OLD AND NEW OCEANS RIVERS SHADOWS STORMS THE EARTH?S CRUST THE STORY OF A NAIL THINGS THAT SPIN why?

A Book of Reasons

why and how?

A Second Book of Reasons

YOUR EARS YOUR EYES

© 1963 by Irving and Ruth Adler All rights reserved. This book, or parts thereof, must not be repro¬ duced in any form without permission. Published by the John Day Company, 62 West 45th Street, New York 36, N.Y., and simul¬ taneously in Canada by Longmans Canada Limited, Toronto. Library of Congress Catalogue Card Number: 63-14504 MANUFACTURED IN THE UNITED STATES OF AMERICA

0080-0100

u S. 1255048 Contents Air on the Move Wet Air

6 8

Where Cold Air and Warm Air Battle

10

Thunderstorms

12

Hailstorms: Ice from the Sky

16

Warm Front Weather: Rain, Rain, Rain

18

Cold Front Weather: Squalls and Thunderstorms

19

Blizzards

20

Ice Storms

22

Cyclones and Cyclone Storms

24

Hurricanes

26

Typhoons and Their Sisters

30

Tornadoes

32

Waterspouts

34

Floods

36

Black Blizzards

38

Dust Devils

41

Many Kinds of Winds

42

Fire Storms

44

Trying to Stop Storms by Magic

46

Word List

47

RAINSTORMS BRING FLASH FLOODS, KILLING 330 STORM CAUSES GREAT DAMAGE. GALE WINDS TOPPLE TREES, CUT OFF POWER. These are headlines of newspaper stor¬ ies. The stories tell about two September

p

storms in 1962. The storms happened two days apart at places 3000 miles apart. The first storm happened in Spain. The second storm happened in the northeastern part of the United States. Storms may happen any day of the year. But there are some storms that happen most often during certain seasons. Storms may happen anywhere on the earth. But there are some storms that hap¬ pen only in certain places. There are some storms that happen only in deserts and other dry places. There are some storms

Storms may bring thunder and light¬ ning. Storms may have strong winds. Storms may bring rain, snow, hail, sand, dust, ice or sleet. Storms may even bring fire. Storms are very fierce. Many storms cause a lot of damage. But storms can also play funny pranks. Storms are known by many names. They have different names in different places and seasons. Storms are part of the earth’s weather. All weather happens in the shell of air that surrounds the earth. This shell is about 800 miles thick. But weather happens only in the very bottom layer of this shell. This bottom layer is only 10 miles thick. Above this bottom layer, the sky is always blue and there are no clouds. Above this botIaye

'never any:storms.

Sp; -

*

4/ V

The same amount of sunlight is spread out over more surface near the poles...

Air on the Move

Weather is made when air moves. The heat of the sun makes air move. The heat of the sun warms up the surface of the earth. It warms up the land and the oceans. It warms up some parts of the earth more than other parts of the earth. The heat of the sun warms up parts near the equator more than it warms up parts near the North and South Pole. The warm surface of the ground warms the air above it, the way a stove warms the air above it. When air gets warmer, it gets lighter. 6

Air that is cooler is heavier. Heavier cooler air sinks down to the ground. It pushes under lighter, warmer air. So lighter warmer air begins to rise in the same way as a balloon rises. It is pushed up by heavier air around it. The weight of air makes it press down on the ground. How hard the air presses down at a place is called the air pressure (PRESH-er) at that place. Air does not press down as hard at places where air is rising as it does at places where air is sinking. So air pressure is lower at places where air is rising than it is at places where air is sinking. A place of high pressure is called a high for short. A place of low pressure is called a low. When air moves, it makes a wind. Winds always move from high pressure places to low pressure places.

7

Wet Air Air has many gases in it. One of the gases in air is water

vapor (VAY-per). Another name for water vapor is steam. You can see for yourself that air has water vapor in it. Put a few ice cubes into a glass. Then fill the glass with cold water. Now watch the outside of the glass. The out¬ side of the glass begins to look cloudy. Tiny droplets of water are forming on the outside of the glass. The drop¬ lets of water have come from the air around the glass. The cold surface of the glass has changed some of the water vapor in the air around the glass into the tiny drop¬ lets of water that you can see. How much water vapor there is in air depends partly on how warm the air is. Air that is warm can hold more water vapor than air that is cold. The experiment you just did with the glass of ice water shows that this is so. The cold outside of the glass made the air next to it cold. The cold air next to the glass could not hold all the water vapor that was in it. So some of the water vapor changed to water. How much water vapor there is in air depends also on where the air is. Air over the ocean usually has more water vapor in it than air over land. This is because some of the water of the ocean is being changed to water vapor all the time. When air rises, it gets cooler. As air cools, it can hold 8

less water. The water vapor may change into droplets of water. Droplets of water high up in the air are clouds. If the clouds form very high up, where it is freezing cold, the water vapor does not change into droplets of water. It changes into ice crystals (KRISS-tulls). Some clouds are made of ice crystals. Ice crystals that get very big fall to the ground. When this happens, it snows. If the heavy ice crystals pass through warm air as they fall, they may melt. Then it

rains. Rain sometimes falls, too, when the droplets of water inside a cloud get very heavy, and fall to the ground.

Snow flakes

Air masses over North America in the summertime

Where Cold Air and Warm Air Battle Air over northern Canada and northern Europe is cold and dry. Air over the North Atlantic Ocean and air over the North Pacific Ocean is cold and wet. Air near the equator is very warm. Air over the South Atlantic Ocean, the South Pacific Ocean and the Gulf of Mexico is warm and wet. Air over northern Africa is warm and dry. Cold dry air, cold wet air, warm dry air and warm wet air are all different kinds of air masses. 10

The air mass over northern Canada sometimes moves down over the United States. The air mass over northern Africa sometimes moves up over Europe. When an air mass moves into a place, it brings its own special kind of weather with it. When cold dry air comes in from the north in the wintertime, it brings a cold spell. A warm, wet air mass during the summertime brings hot, sticky weather with it. Where two air masses meet, there is a front. There is a

warm front where a warm air mass pushes into the place where a cold air mass is. There is a cold front where a cold air mass pushes into the place where a warm air mass is. Each kind of front brings its own kind of weather. Sometimes fronts bring storms with them. The weather of the United States is very changeable. It may change from day to day and even from hour to hour. Mark Twain said that once on a spring day he counted 136 changes of weather in New England! The changeable weather is the result of a battle that is going on all the time between two air masses. There is a battle going on all the time between cold air coming from the north and warm air coming from the south. The front be¬ tween these two air masses keeps moving back and forth. The moving front keeps changing the weather of the places over which it passes. 11

Thunderclouds Thunderstorms On hot summer days the hot ground warms the air above it. The warm air rises, getting cooler all the time. It rises until it reaches the level where some of the water vapor changes into droplets of water or rain, forming a cumulus (KYOU-myou-lus) cloud. Cumulus clouds are round and fluffy. If the air is very wet, a cumulus cloud may grow into a thundercloud. At first the air inside a cumulus cloud is warmer than the air around it. So the air inside the cloud keeps rising. It rises faster and faster, making a strong upward wind inside the cloud. The wind makes the cloud grow upward until the cloud is about 7 miles high. The 12

top of the cloud is in the layer where water freezes into ice crystals or snow. When the top of the cloud is as cold as the air around it, the cloud stops growing upward. For this reason the top of the tall cloud is flat. This tall, flattopped cloud is now full of ice crystals and drops of water. It is now a thundercloud. Some of the drops of water inside the thundercloud be¬ come so heavy that they begin to fall as rain. The falling rain drags down cold air with it from high up. This makes a strong cold downward wind inside the cloud. This cold wind makes it suddenly get cold on the ground. The strong upward wind and the strong downward wind inside the same cloud knock the raindrops about. Some of the raindrops are broken into bits. This knock¬ ing about gives them charges. In this way the thunder¬ cloud gets an electric charge. If the charge in a thundercloud gets very big, it can jump to another cloud or to the ground. When this hap¬ pens, there is a great spark. The spark is lightning. Lightning heats the air through which it passes. The air gets so hot that it explodes. Thunder is the noise of the explosion. Thunder and lightning happen at the same time. It is never safe to be caught in a thunderstorm. Air¬ planes that have been caught in thunderstorms have sometimes been broken in two by the strong up-and-down 13

Lightning winds inside the thundercloud. The winds work like a giant pair of scissors. People and animals that have been caught in thunderstorms have sometimes been hurt and even killed by the lightning. Trees have been split in two by lightning. Houses struck by lightning have caught fire. Lightning jumps most easily from a cloud to tall pointed objects and to metal objects on the ground. If you are caught in a thunderstorm, it is best to stay away from hilltops and from trees that stand all alone. It is best to stay away from metal fences. 14

Lightning rods on the roof of a house can protect the house against lightning. The sharp ends of the rods are taller than the house. Lightning near a house will strike the lightning rod instead of the house. Heavy wires carry the electric charge to the ground where it cannot do any harm. If you are safe inside, it is fun to watch a thunderstorm. You can even tell how far away the storm is. The flash of light from a stroke of lightning travels so fast that you see the lightning almost as soon as it happens. But the sound of the thunder travels more slowly. It takes the sound of the thunder five seconds to travel one mile. So you hear the thunder after you see the lightning. If you count the number of seconds between the lightning and the thun¬ der it makes, you can find out how far away the storm is. If you count 5 seconds, the storm is one mile away. If you count 10 seconds, the storm is two miles away. If the lightning and thunder happen at the same time, the storm is overhead. You can count seconds without a watch by saying slowly “a thousand and one, a thousand and two, a thousand and three,” and so on, instead of just “one, two, three... Thunderstorms usually do not last very long. But the rain of a thunderstorm is usually very heavy. Sometimes the rain is so heavy that an inch of rain may fall in one minute. Then we say there is a cloudburst. 15

This hailstone was blown back to the freezing layer four times

Hailstorms: Ice from the Sky Sometimes the upward winds inside a thundercloud are so strong that they keep the rain from falling to the ground. As the rain falls inside the cloud, it is blown up again. It may be blown high up to the freezing layer where it changes into a little ball of ice. Drops of water in the cloud freeze on the ball of ice to make a shell of ice around it. The shell makes the ball larger and heavier. When the ball is heavy enough, it begins to fall again. But the strong upward winds inside the cloud may carry it up to the freezing layer once more. Each time the ice ball is carried up to the freezing layer, another shell of ice is wrapped around it. In this way the ball of ice gets bigger and bigger. Finally the ice ball gets so big that the winds cannot keep it up any more. Then it falls to the ground as a hailstone. If you cut open a hailstone, you can see the different shells of ice. If you count the shells, you can find out how many times the hailstone was blown back to the freezing 16

layer before it finally fell to the ground. Hailstones can keep growing until they are 5 or 6 inches across. In 1928 hailstones as big as grapefruit fell over a small part of the state of Nebraska. One hailstone weighed 1% pounds. Hailstones can do a lot of damage when they are very big. In July 1952, hail, carried by winds of 100 miles per hour, did great damage to the tobacco fields in the Con¬ necticut River Valley. The hail was like a giant knife that cut down the tobacco plants. In September 1952, large hailstones piled up on a highway in Nebraska until they were 3 or 4 feet deep. Snowplows had to be brought out to push the pile of hailstones off the road. In 1936, a group of Bushmen of South Africa was caught in a heavy hailstorm. The large hailstones killed them. The men were found buried under three feet of hail.

Warm Front Weather: Rain, Rain, Rain When warm air moves into a place where cold air is, it begins to climb up over the cold air. It is as though the warm air is climbing up a hill of cold air. This makes the warm front, where the warm air and the cold air meet, slope upward toward the cold air. The front slopes just a little bit, like a hill that is not steep. As the warm air climbs up the slope it becomes cooler and clouds form. The clouds form in big flat sheets. Clouds like this are called stratus (STRAY-tus) clouds. The warm air keeps climbing up the slope all the way to the level where ice crystals form. Clouds that form at this level are so thin that you can see through them. These are cirrus (SEAR-rus) clouds. When a warm front moves in, here is what it looks like. First you see high thin cirrus clouds. As the front comes closer, it seems as though the roof of clouds gets thicker and lower. The lowest layer of clouds brings rain that may fall for several days. Then the skies begin to clear Stratus r.Ini ids

Warm air

Cold air

Warm front 18

slowly. The air is much warmer. The warm front storm has passed leaving a warm air mass behind.

Cold Front Weather: Squalls and Thunderstorms When cold air moves into a place where warm air is, it pushes under the warm air. Then the warm air is pushed up quickly. So the slope of a cold front is very steep. When warm air rises quickly like this, the clouds that form grow upwards. So these cold front clouds are cumulus clouds. The storm they bring has strong, gusty winds. It is called a line squall (SKWALL). In the sum¬ mertime, a line squall may take the form of thunder¬ storms. In the wintertime, a line squall may be a howling blizzard. After a cold front has passed, the sky clears quickly. The temperature drops suddenly. Once, in the northern part of the United States, a cold front made the tempera¬ ture fall 60 degrees in two hours.

o

2. cl

CANADA

t Warm moist air PACIFIC OCEAN

UNITED SWES

Dry cold air from Canada meets wet warm air of the Pacific making a cold front Blizzards are cold front storms

Blizzards In the wintertime blizzards often sweep across the states in the midwestern part of the United States. They come with fierce winds. They leave behind freezing cold, deep snow, great damage and even death. These midwestern blizzards are cold front storms. They happen when it is colder than usual over the north¬ ern part of Canada and when the Pacific Ocean is warmer 20

than usual. Then dry cold air from Canada moves down quickly over the midwestern part of the United States. There the dry cold air mass meets a warm wet air mass that is moving east from the Pacific Ocean. Their meeting place is a cold front. The cold air changes some of the water vapor in the wet Pacific air into heavy snow. Fierce winds blow the snow into deep snowdrifts. One of the worst blizzards that hit the Midwest hap¬ pened in January 1888. The snow was so thick that peo¬ ple could not see and lost their way. Children lost their way and froze to death on their way home from school. Farmers and farm animals froze in the fields. Travelers lost their way and were buried under snowdrifts. 235 people died in the storm. Sometimes blizzards even hit the eastern part of the United States. In March 1888 a great blizzard swept over parts of Pennsylvania, New Jersey, New York and New England. It dropped so much snow that snowdrifts, in some places, were 40 feet deep. Telephone and telegraph lines were blown down by the strong winds. Boston, Massachusetts, was cut off from the cities around it. Until the lines were fixed, messages from Boston had to be sent to New York by way of England, using the cable under the Atlantic Ocean. More than 400 people died as a re¬ sult of this blizzard. 21

Ice Storms Ice storms are warm front storms that sometimes hap¬ pen in the wintertime. For an ice storm to happen, the warm front must form between a warm wet air mass and a freezing cold dry air mass. There must also be rain fall¬ ing through the warm wet air. The picture shows what happens. The rain passes through the front into the freezing cold air. Because the front is a warm front, it slopes only a little bit. So there is only a thin layer of freezing cold air between the sloping warm front and the ground. The freezing cold air makes the ground freezing cold. When the rain passes through the cold air, it is made very cold. Then, as soon as the rain touches the ground it freezes right away. The freezing rain covers everything it touch¬ es with a coat of ice. As long as the rain lasts, the coat of ice gets thicker and thicker. It may grow until it is 4 or 5 inches thick. Ice storms are very beautiful. Ice-covered twigs look like bright jewels. But ice storms are very terrible, too. The icy surface of roads makes automobiles skid. So driv¬ ing is not safe. Sidewalks become slippery, making it dan¬ gerous for people to walk on them. Ice-covered branches may crash under their load of ice, blocking roadways. 22

crushing cars and hurting people. Ice-covered electric and telephone lines may snap under their load of ice. Then people have to do without electricity and all the things for which they use electric power. They have to do without telephones and cannot call for help if they need it. In the middle of the winter, ice storms in the United States happen most often in the southern states.

The work of an ice storm 23

Cyclones and Cyclone Storms Sometimes the air over thousands of square miles of ground begins to whirl around slowly. The whirling air is called a cyclone (SY-klone). There is a storm at the cen¬ ter of a cyclone. Cyclones form often over the United States and Europe. They travel over the ground from west to east. Cyclones form at a front where warm air lies next to cold air. The wind in the warm air mass usually moves toward the east. The wind in the cold air mass usually moves toward the west. The first picture shows the two air masses and the front between them. For some reason a dent or wave forms in the front. The dent makes some of the cold air move in the direction of the green arrows in the second picture. The cold air be¬ gins to push under the warm air. This makes a cold front. The warm air begins to move in the direction of the white arrows. The warm air begins to climb up the cold air. This makes a warm front.

Cold air

■■■■■■■■■■■■

FRONT

How a cyclone forms

Warm air 1

The dent in the front keeps getting bigger. This makes winds that spin around in a circle. The cyclone has formed. The third picture shows what it looks like. The winds of a cyclone spin around the center of the cyclone. The center is always a place of low pressure. The winds blow toward the center as they spin. North of the equator, the winds always turn opposite to the way the hands of a clock turn. Using this fact, you can always tell where the low pressure center of a cyclone is. If you face the wind, the “low” will always be on your right. As it moves over the ground, the center of a cyclone carries a storm from place to place. You can tell a cyclone storm because it brings quick changes in temperature, pressure and the direction of the wind. First there will be warm front weather followed quickly by cold front weather. First there may be warm front rain. Then there may be clear weather followed quickly by squalls or blizzards. A cyclone is often more than 1,000 miles across. Its winds are usually around 25 miles per hour.

Hurricanes Hurricanes are storms of great fury. They bring strong winds and heavy rains. The strong winds can smash houses and uproot trees. The strong winds, blowing against the sea, can make great storm waves that flood the land. Hurricanes of the North Atlantic Ocean are bom over the warm seas near the West Indies. They are born when these seas are warmest. These seas are warmest in the early fall. So most hurricanes are born in September or October. The hot sun, beating down on the seas near the equa¬ tor, changes tons of water into water vapor. The water vapor rises into the air. The heat in the water vapor is the power that gives a hurricane its fury. At the center of a hurricane is a calm, clear place of low pressure. This is the eye of the hurricane. The eye is usually no more than fifteen miles wide. Winds from high pressure places rush in toward the eye. The winds spin around the eye in the same way as the winds of a cyclone spin around the center of a cyclone. The mass of spinning winds may be 500 miles across. The hurricanes that begin south of the equator have winds that turn in the same direction as the hands of a clock. The hurri¬ canes that begin north of the equator have winds that turn in the opposite direction. 26

Each year the Weather Bureau names hurricanes when they are born. They are given girls’ names in alphabetical order. Although each hurricane has a different name, it behaves very much like other hurricanes that are born in the same place. The hurricanes of the North Atlantic Ocean always travel west at first over the West Indies until they reach the coast of the United States. Then they turn north or northeast and go out to sea. The paths of hurricanes may be a few thousand miles long. Usually their paths do not take them over places where people live. Sometimes hurricanes follow unexpected paths. The hurricane of September 1938 traveled over the ocean un¬ til it reached New York. Then it raced across Long Island and New England and finally ended in Canada. Its storm

Damage done by Hurricane Carol in August 1954

wave battered the shores of Long Island and Connecticut. More than 600 people died in the storm. Trees were up¬ rooted. Houses were damaged and even washed away by the storm wave. Power lines were knocked down. The winds reached 183 miles per hour. In September 1900, a hurricane reached Texas, near the city of Galveston. The winds of the hurricane whipped the water of the Gulf and made a great storm wave. The storm wave washed over the city of Galveston. More than six thousand people were drowned. In November 1932, a hurricane struck the coast of Cuba. The storm wave of this hurricane flooded the town of Santa Cruz del Sur. The storm wave killed two thousand five hundred of the four thousand people in the town. The strong winds of a hurricane sometimes do strange things. In 1928 in Puerto Rico a hurricane wind picked up a heavy pine board and drove it right through the trunk of a palm tree. The winds of a hurricane may, for a few moments, be as high as 250 miles an hour. Luckily, a hurricane itself moves only about ten miles an hour. This means that it may be more than a week between the time a hurricane is bom over the warm sea and the time it dies after its energy is used up. Weather Bureau stations have plenty of time to watch the hurricane. They can guess at the path it will follow and warn people who may be in its way. 28

A hurricane wind drove the board right through the 29

Typhoons and Their Sisters There are storms like hurricanes that form over almost all the warm oceans of the world. The hurricanes that strike China, Japan and Vietnam are called typhoons (ty-FOONS). The hurricanes that strike India are known 30

as cyclones. The hurricanes of Australia are called willy-

willies. The hurricanes of the Philippine Islands are called baguios (BAH-gyohs). Willy-willies form south of the equator. So the spinning winds of willy-willies turn in the same direction as the hands of a clock. Typhoons, baguios and cyclones have killed more peo¬ ple than the hurricanes of the West Indies. This is prob¬ ably because there are hundreds of millions of people who live in the paths of these storms. Many cyclones that strike India begin in the Bay of Bengal. The most terrible cyclone on record hit India in October 1737. The cyclone built up great storm waves in the Bay of Bengal. The Hooghly (HOOG-lih) River flows into the Bay of Bengal. Storm waves rolled up into the Hooghly River. One wave rose to a height of forty feet before it crashed down on the land. More than three hundred thousand people were killed by this storm wave. In 1881 a typhoon that started over the South China Sea built up a great storm wave. The storm wave flooded the city of Haiphong (hih-FONG) in Vietnam. Three hundred thousand people were drowned. In September 1959 typhoon Vera smashed against Honshu, the largest island of Japan. It flooded the harbor of the city of Nagoya, drowning thousands of people. Almost one million people were made homeless by the storm. More than four thousand people were killed.

/

Tornadoes Tornadoes are the fiercest of natural storms. Like cy¬ clones and hurricanes, they are masses of spinning air. The spinning air of cyclones and hurricanes usually cov¬ ers hundreds of miles. The spinning air of tornadoes is usually no more than one mile across. Tornadoes last only for a few minutes. Tornadoes have their beginning in upside-down air. In reading about fronts, we saw that when a warm air mass and a cool air mass are side by side the cool air usually pushes under the warm air. Sometimes cool dry air moves

over warm moist air instead. But the cool dry air is heav¬ ier than the warm moist air. So it tends to sink, pressing down on the warm moist air under it (1). When this happens a tongue of cool air may break into the warm air (2). Then the lighter warm air around the tongue will begin to climb up the tongue. As the warm moist air climbs up the tongue, it cools. The cooling changes some of the water vapor in the warm air into droplets of water that can be seen. Then the tongue can be seen as the funnel-shaped cloud of a tornado (3). Air right under the funnel keeps moving in to take the place of the warm air that flows into the funnel. In this way the funnel reaches lower and lower until it touches the ground. In this way the spinning winds of the tor¬ nado are formed. 32

In the center of the funnel, air rushes upward at a great speed. The upward-moving wind inside a tornado funnel may reach 500 miles per hour. This makes a tornado act like a giant vacuum cleaner. The funnel sucks up any¬ thing that happens to be in its path (4). The dust and dirt sucked up by the funnel make it look black. So a tornado can be seen easily, even if it is far away.

Cold dry air

Warm moist air

Warm moi

moist air

How a tornado is formed 33

The funnel of a tornado Tornadoes do a great deal of damage. They also do many strange things. They have picked up farm animals and set them down, unhurt, hundreds of feet away. In June 1953 a tornado picked up a heavy truck and carried it four hundred feet. The truck was found, but no one ever saw its driver again. There are parts of the United States which tornadoes visit often. The states of Kansas, Nebraska, Iowa, Texas and Oklahoma are tornado country. People can make themselves safe against tornadoes in storm cellars.

Waterspouts Tornadoes that form at sea are called waterspouts. Waterspouts usually are not as fierce as tornadoes. The 34

CJ. a 1255048 funnel of a waterspout, like the funnel of a tornado, is a whirling cloud. At the bottom of the funnel, there is a little hill of water that has been pulled upward by the sucking winds inside the funnel. Waterspouts travel slowly. So ships can easily steer out of their way. Sometimes a waterspout may suck up a great deal of sea water into its funnel. Then strange things may happen. A great waterspout formed near Martha’s Vineyard in Mas¬ sachusetts in August 1896. After the waterspout died, salty rain fell from the clouds. We sometimes say, when it is raining heavily, that “it is raining cats and dogs.” Of course this has never hap¬ pened. But once it did rain live fishes three inches long. This was the work of a waterspout in India in 1839.

A waterspout 35

Floods can be stopped by... planting 'trees...

■ • • and building dams in high places...

Most of the floods that happen are caused by weather that isn’t as exciting as a hurricane or a typhoon. Most of the floods that happen are floods that can be controlled. Bad floods may happen at any time. They may happen when a cyclone with a very wet warm air mass stops mov¬ ing. Then the warm front rain falls steadily for days and days. Usually when rain falls, much of it sinks into the ground. Sometimes most of the rain runs off, instead, filling streams and rivers. Then the swollen rivers over¬ flow their banks, causing floods. Rain can sink into the ground if the ground can act like a sponge. The roots of trees and grasses help the 36

ground do this. If high places are kept covered with trees and grasses then much of the rain that falls will not run off. The worst floods caused by rain have happened in China. In 1887 a million people were drowned in a flood of the Yellow River. In 1911 one hundred thousand people were drowned in a flood of the Yangtze River. The worst flood of this kind in the history of the United States happened in 1889. The flood was the result of a heavy spring downpour and man’s thoughtlessness. Some rich people in Pittsburgh, Pennsylvania, had built a tall earth dam to make a private lake in the valley above the city of Johnstown. The heavy rains burst the dam. A mountain of water poured out of the lake flooding Johns¬ town. Twenty-two hundred people were drowned. Flash floods are caused by heavy rains that often come with thunderstorms. They usually happen at the end of steep narrow valleys. So much rain falls so quickly dur¬ ing a cloudburst that the level of the streams in the valley rises very fast. Then the water pours out over the mouth of the valley, flooding it. There are two ways of keeping floods from happening. One way is by planting trees and grasses in the high places where streams and rivers begin. They help the ground hold the rain water so that it doesn’t run off at once and cause a flood. The second way is to hold back flowing water by dams in high places and high banks along rivers in low places. 37

Black Blizzards The Great Plains region of the United States lies be¬ tween the Rocky Mountains and the states along the Mississippi River. The Great Plains region is the home of the black blizzard. The black blizzard is a storm with strong winds. It is “black” because the winds do not carry snow. They carry dust. Black blizzards are also called dust storms. Dust storms are caused by nature and man working together. The winds that blow over the Great Plains are usually dry. They become dry when they climb over the Rocky mountains from the Pacific Ocean. From time to time little rain falls on the Great Plains. Then plants die. When this happens, there is a drought (DROUT). Now there are no plants to keep the hot sun

A dust storm

from baking the soil. The hot soil gets dry and turns to powder. The winds get hotter and drier. The hot dry winds pick up the powdery soil and carry it through the air. The sky becomes black. Great dust drifts pile up, covering buildings and small trees. The wind and drought are nature’s work. Weathermen do not understand why there is little rainfall over the Great Plains during certain years. The dry, powdery soil is man’s work. Ever since the first settlers began to do farming on the Great Plains, they did the wrong kind of farming in some places. Some of the soil is not very good. It needs a cover of grass all the time to keep the hot sun from beating down on it. So it should be used only for grazing animals. But farmers can earn more money if they plant row crops. When there is enough rain, they can plant row crops on the poor soil without much damage. When there is a drought, the bare soil between the rows is baked by the sun. It becomes dry and powdery. Then the stage is set for dust storms..

Some land should be used only for grazing

The powdery, dry soil is blown by the wind The Great Plains region of the United States is not the only place where dust storms are bom. Storms in Egypt, along the Red Sea, may carry huge amounts of dust. 40

These storms are called haboobs (hah-BOOBS). Haboobs may be ten or twenty miles wide and several thousand feet high. They travel at about 30 miles per hour. So be¬ ing caught in a haboob can be very unpleasant.

Dust devils Along dusty country roads in the summertime, you may see little clouds of spinning dust. These little whirls are the baby cousins of the dust devils of hot deserts. A dust devil begins over an especially hot spot in the desert. The hot air over this spot begins to rise. Air around the hot spot flows in to take the place of the rising air. As the air flows in, it begins to whirl around the hot spot. The closer the air gets to the center of the whirl, the faster it spins. The whirling air picks up the light desert sand. It car¬ ries the sand higher and higher, as the spinning air rises. The spinning mass of sand can be seen easily. This spin¬ ning mass of sand is a dust devil. It may be one thousand feet high. A dust devil is usually only a few feet wide. It moves slowly, so it is easy to get out of its way. It usually has little power, so it doesn’t do much damage. It can suck up light things like scraps of paper the way the funnel of a tornado sucks things up. 41

Many Kinds of Winds Winds blow all over the world. They may be wet or dry. They may be cold or warm. They may carry dust, sand, and even tiny shells. Winds bring changes in weather with them. They may also bring storms. The winds in different parts of the world are called by different names. We will name some of them here and tell what they are like. A harmattan (har-ma-TAN) is a hot dry land wind of the west coast of Africa. The wind carries tiny shells that are too small to see. The tiny shells can hurt plants. An¬ other name for the harmattan is the doctor because it heals certain skin diseases. A simoon (sih-MOON) is a hot dry wind of the sandy deserts of Asia and Africa. It carries clouds of whirling sand. It can bury people and animals in the desert. When a simoon blows across the Mediterranean Sea to Italy, it is called a sirocco (sih-ROCK-oh). In Turkey it is called a samiel (SAM-yell). A samiel is a wet wind. In Spain it is called a solano (so-LAH-no). A khamsin (KAM-sin) is a hot dry wind over Egypt. It comes from the southwest. A brick-fielder is a hot dry dusty wind of Australia. A Santa Ana is a dusty winter gale wind of California. A levanter (lee-VAN-tur) is a strong east wind at Gibraltar. 42

A mistral (MISS-tral) is a cold dry wind in the south of France. It blows down from the north. A wind like the mistral is called a bora (BO-ra) in Yugoslavia. A chinook (shih-NOOK) is a warm dry wind that blows down the eastern slopes of the Rocky Mountains. When it blows the temperature may go up as much as 40° in one hour. So it is also called the “snow eater” because it quickly melts any snow in its path. A foehn (FERN) wind is like a chinook. It usually blows down the north¬ ern slopes of the Alps mountains in Europe. 43

Fire Storms There is a storm that is fiercer than the fiercest hur¬ ricane or tornado. This storm is a man-made storm. It is the kind of storm that was started during World War II by atom bombs and incendiary (in-SEN-dih-ary) bombs (fire bombs). It is the kind of storm that will be started if hydrogen bombs are ever used. It is called a fire storm. Fire storms are terrible because they have the energy of a hurricane. They are terrible because this energy is used up in a short time and in a small space. They are terrible because of their great heat. When an atom bomb or a hydrogen bomb is dropped, there is an explosion. Heat rays are given off by the ex¬ ploding bomb in the same way as heat waves are given off by an electric broiler. The heat is so great that things like dried leaves, paper and thin pieces of wood start to burn. The fire then quickly spreads and soon anything that can bum is on fire. A fire storm covers a great surface. A fire storm started by incendiary bombs in 1943 in the city of Hamburg, Germany, killed 40,000 people and burned half of the buildings in the city. The fire storm started by the atom bomb that was dropped on the Japanese city of Hiro¬ shima in 1945 was about three miles across. If a hydrogen bomb is ever used, it can make a fire storm that could

44

cover the whole state of Vermont. A fire storm starts great whirling winds. The hot air of the great fire shoots upward at the center of the fire. Fresh air from outside the fire storm rushes in to take the place of this rising air. This starts a great hot hurricane. The fire storm of Hiroshima started a tornado. There is no way to stop fire storms once they have started. The only way to stop them is not to use incendi¬ ary bombs, atom bombs or hydrogen bombs at all.

If a large hydrogen bomb explodes eight miles up....

-120 miles.... it will start a fire 120 miles across

45

Trying to Stop Storms by Magic In the past people did not understand how storms be¬ gan. They thought storms were started by evil spirits. So, to stop storms or to keep storms from happening, people thought they had to do special things to fight the evil spirits. In Africa, men, with knives, ran after dust devils. They thought that if they stabbed the evil spirit in the middle of the dust devil, the dust devil would go away. In Greenland, the people believed that a woman who had just had a baby could stop a wind. All she had to do, they thought, was to go outside and fill her mouth with air. Then, when she came back inside, she had to blow the air out again. Among some American Indians, a girl never combed her hair outside her house. To do so, they thought, would start a storm. Among the Romans a long time ago, a sailor was not allowed to cut his hair or his nails except during a storm. If there was no storm, they thought he would start one by cutting his hair or nails. During a storm, it didn’t matter. In some parts of France and Germany people still be¬ lieve in the old ideas. They think that if they put a piece of burned wood under their beds at Christmas time, it will make them safe from thunder and lightning. Now that we have a science of weather, we know that 46

charred logs, deep breaths and hair-combing cannot stop or start storms. We don’t know how to stop or start storms. But we can try to keep the storms from harming us.

Word List Air Pressure at a place.

—

(PRESH-er) — How hard the air pushes down

Cirrus clouds — (SEAR-rus) — Thin clouds that form high up. You can see through them. Cumulus clouds — (KYOU-myou-lus) — Round fluffy clouds that form high up. Drought — (DROUT) — A time when there is little rain and crops die. Eye of a hurricane — The calm clear place of low pressure in the center of a hurricane. Front — A place where a cold air mass and a warm air mass meet. Hailstone - A ball of ice that falls to the ground during some thunderstorms. Ice crystals — (KRISS-tulls) - What water vapor turns into high up where it is freezing cold. Ice crystals that fall to the ground are snow. Lightning - The spark when an electric charge jumps from one cloud to another or from a cloud to the ground. Stratus clouds — (STRAY-tus) — Clouds that form in big flat sheets. Thunder - The sound of exploding air caused by lightning. Thundercloud - A tall flat-topped cumulus cloud that brings thunderstorms. Wind — Air that is moving. 47

About the Authors Irving and Ruth Adler have written more than three dozen books about science and mathematics. Dr. Adler has been an instructor in mathematics at Columbia Uni¬ versity and at Bennington College, and was formerly head of the mathematics department of a New York City high school. Mrs. Adler, who formerly taught mathe¬ matics, science, and art in schools in the New York area, recently also taught at Bennington. In addition to work¬ ing with her husband writing this book, she drew the illustrations. The Adlers now live in the country in Shaftsbury Township, near Bennington, Vermont. Books by Irving Adler alone and books by him in col¬ laboration with Ruth Adler have been printed in 75 dif¬ ferent editions, in 8 languages and in 9 reprint editions.

All photographs by 17. S. Department of Commerce, Weather Bureau

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